Increase Logical C: on Server

[taotao hagu]

how do I increase C: using part of D:

 

[USAFRet]

how do I increase C: using part of D:

Need FAR more info for this.

What OS?
Are these physical drives, or partitions on one drive?
"server" ? For what?
Size of these drives or partitions?
Why are you doing this?